Apparatus for applying electrical current to a user&#39;s leg muscles

ABSTRACT

The invention relates to apparatus for applying electrical current to the quadriceps muscle. The apparatus is in the form of a garment (to be worn on a user&#39;s thigh) having a integrated programmable stimulation device including integral electronics, LCD display, user controls and a battery. To ensure accurate and repeatable positioning of the garment, it is shaped such that it locates above the patella. Furthermore, reference lines are provided on the skin facing surface of the garment to assist the user in the accurate placement of skin engaging electrodes. In combination, the features of the invention provides a safe and convenient means of electrically stimulating the quadriceps muscle irrespective of patient size whilst minimizing the opportunity for error. Moreover, the invention dispenses with the need to employ a skilled clinician to individually place each electrode.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of and claims the benefit of U.S.patent application Ser. No. 10/555,732 filed Nov. 27, 2006, entitled“APPARATUS FOR APPLYING ELECTRICAL CURRENT TO THE NEUROMUSCULAR SYSTEM,”now U.S. Pat. 7,957,816, which is a U.S. National Stage of PCTInternational Patent Application No. PCT/IB2004/001878, filed May 7,2004, which is entitled to priority under 35 U.S.C. §119(e) to G.B.application number 0310414.8 filed May 7, 2003 all of which are herebyincorporated by reference in their entirety herein.

The present invention relates to apparatus for applying electricalcurrent to muscles, particularly, but not exclusively, to the quadricepsmuscle.

Electrical stimulation of the quadriceps muscle is well known. Thequadriceps is the most important muscle to be rehabilitated after anoperation on the knee. It is the strongest extensor of the knee andimproving the force of its contraction after surgery consequently aidsrehabilitation of the other muscles involved in ambulation.

The vastus medialis component of the quadriceps stabilises the patellain the early stages of walking. After knee surgery, not only can therebe a reflex inhibition of this muscle but there can also be a temporarydisruption of the joint receptor activity which interferes with thepatients proprioceptive feedback. Therefore the quadriceps muscle needsadditional assistance in overcoming this inhibition and earlyrehabilitation to aid stability.

Although the quadriceps is a large muscle in the front of the thigh, theknowledge of a clinical professional is required in order to accuratelyposition appropriately sized electrodes according to patient size tothus ensure effective electrical stimulation. The professional mustensure that the correct channels from a stimulator unit are connected tocorrect electrodes on the right or left leg. Whilst previous attempts toproduce a fail-safe garment for electrode application to the body havesucceeded in providing more convenient methods of electrode applicationcompared to traditional lead-wired systems, the assistance of aprofessional has still been required in the initial set-up stage.

A further problem exists in terms of repeatability in user applicationof the garment. This is often inadequate since slight shifts in theposition of the electrode placement from day to day can change theeffectiveness of the stimulation, especially if the garment is placedover a moving joint.

Many muscle groups have a symmetrical group on the other side of thebody across the coronal plane. These muscle groups are mirror images ofeach other and so the electrode placement should take account of this.This has been achieved in certain garment designs before by producing amirror image garment or by turning the existing garment inside out.Where a stimulator unit and wiring is integrated in the garment such asolution is not practical since it would require the user to change thenecessary connections between the stimulator and the electrodes thusintroducing the opportunity for error.

According to a first aspect of the present invention there is providedapparatus for applying an electrical current to a neuromuscular systemcomprising a garment adapted to cover a portion of a user's body, astimulation device for generating a stimulating current connectable toat least one electrical contact on said garment, the garment beingshaped to correspond with a particular anatomical feature to ensureaccurate and repeatable positioning of the garment with respect to theparticular neuromuscular area to be treated.

According to a second aspect of the present invention there is providedapparatus for receiving an electrical signal from a neuromuscular systemcomprising a garment adapted to cover a portion of a user's body, areceiving device connected to at least one electrical contact on saidgarment, the garment being shaped to correspond with a particularanatomical feature to ensure accurate and repeatable positioning of thegarment with respect to the particular neuromuscular area to bemonitored.

Preferably, the garment is marked with one or more reference lines toaid the accurate and repeatable positioning of the garment with respectto a particular neuromuscular area.

Preferably, the neuromuscular area is the quadriceps muscle and theanatomical feature is the patella.

Preferably, the stimulation device is adapted such that it isinteractable with the garment to determine whether it is a left-limb orright-limb garment.

Preferably, the garment has an arcuate shaped edge at its distal end tocorrespond with the top of the patella.

Preferably, the reference line is alignable with a notional lineextending upwardly from the centre of the patella.

Preferably, the garment consists of an undergarment and an over-garment,the undergarment having at least one electrical contact on itsskin-facing surface conductively connected to one or more correspondingelectrical contacts on its opposite surface which, in turn, areconductively connected to contacts on the over-garment.

Preferably, the electrical connections between the undergarment andover-garment are made by stud fasteners which are fixed on and extendthrough the undergarment.

Preferably, a plurality of electrical contacts are provided on theundergarment.

Preferably, the or each electrical contact on the undergarment isconductively connectable to one or more skin engaging electrodes.

Preferably, the or each skin engaging electrode is user replaceable.

Preferably, four skin engaging electrodes are employed.

Preferably, at least one skin engaging electrode has a different surfacearea from the other skin engaging electrodes.

Preferably, the combined surface area of the electrodes is at least 300cm².

Preferably, the electrode having the greatest surface area extendsacross the upper quadriceps.

Preferably, at least one of the remaining electrodes covers at leastpart of the lower fibres of the vastus medialis.

Preferably, at least one of the remaining electrodes covers at leastpart of the lateral fibres of the quadriceps.

Preferably, one of the skin engaging electrodes is generally dog-legshaped.

Preferably, at least one of the skin engaging electrodes is generallyrectangular in shape.

Preferably, printed outlines of the skin engaging electrodes areprovided on the skin-facing surface of the undergarment to aid accuratepositioning of the electrodes by the user.

Preferably, the skin engaging electrodes are displaced circumferentiallyto establish current pathways which transect the neuromuscular area.

Preferably, the stimulation device includes control means forselectively directing a stimulating current to one or more of the skinengaging electrodes.

Preferably, the control means includes user programmable software forcontrolling the duration of the stimulating pulses and their sequencingbetween the skin engaging electrodes.

Preferably, the control means includes user programmable software forselecting any subset or all of the skin engaging electrodes in thegarment to form one electrical pole and any other subset or all of theremaining skin engaging electrodes in the garment as the oppositeelectrical pole.

Preferably, the control means includes user programmable software whichallows the user to map control buttons on the garment such that currentapplied to the medial and lateral quadriceps muscles is controllable bymedial and lateral control buttons respectively.

Preferably, the or each contact on the over-garment is conductivelyconnected to the stimulation device of the first aspect.

Alternatively, the or each contact on the over-garment is conductivelyconnected to the receiving device of the second aspect.

Preferably, the garment is securable to a user's body by hook and loopfasteners.

Preferably, the garment is configurable for use on the left or rightleg.

Preferably, the connections between the stimulation device and the atleast one electrical contact on said garment are preset andnon-alterable by the user.

Preferably, the connections between the stimulation device and the atleast one electrical contact on said garment are non-alterable by theuser by virtue of the fact that they are integrated within the garmentitself.

An embodiment of the present invention will now be described, by way ofexample only, with reference to the following drawings, wherein:

FIG. 1 shows apparatus for applying current to the quadriceps(undergarment and over-garment);

FIG. 2 shows the inner and outer surfaces of the undergarment;

FIG. 3 shows the inner and outer surfaces of the over-garment;

FIG. 4 shows the positioning of replaceable electrodes on the leg;

FIG. 5 shows the apparatus in use; and

FIG. 6 shows the electrode sequencing of the apparatus.

FIG. 1 shows apparatus for applying an electrical current to aneuromuscular system, said system being the quadriceps muscle,comprising an undergarment 12 provided with reference lines 14 and 16respectively. A distal end 18 of the undergarment is provided with anarcuate shaped portion 20.

The term neuromuscular is to be understood to include muscles, muscleparts, muscle groups, nerves or a combination thereof.

The apparatus therefore locates unambiguously with an appropriateanatomical landmark. The anatomical locating means and correspondinganatomical landmark must be selected such that the variation indisplacement of electrode positions with respect to the anatomicallocation means is minimised for individuals of different size. Thisallows a common design to be used by different individuals with minimaladjustment.

Typically, a useful anatomical reference is provided by a “bony”reference point on the body where the muscle position with respect tosuch a reference point is consistent between individuals. According tothe present invention, the muscle and bony reference point is thequadriceps and the patella respectively. The patella is a sesamoid boneof the quadriceps muscle and so, by effectively being part of thismuscle, it has a direct relationship to its movement. Regardless of thesize of the patient, the lower fibres of the quadriceps insert via thequadriceps tendon and then into the patella. The lower lateral fibresinsert just above and laterally with respect to the patella. The vastusmedialis inserts a little lower on the medial side.

Accordingly, when designing a garment (see FIG. 1) to assist withquadriceps electrode placement it has been found that the followingcombination ensures correct location in two axes: (i) an anatomicallocating means comprising an arcuate shaped edge 20 corresponding to theupper portion of the patella; and (ii) a reference line 16 through themid point of the patellar curve and along the midline of the thigh.

It will be appreciated by those skilled in the art that the fitting ofundergarment 12 to the leg and positioning it with the aid of thereference line 16 and the arcuate shaped portion 20 can be performed bythe user without any professional assistance.

FIG. 2 shows both the inner (skin facing) surface 30 and outer surface32 of an undergarment adapted for use on the right leg. Reference lines34 are provided on the inner surface 30 corresponding to the shapes ofreplaceable electrodes A, B, C and D for contacting the skin (discussedfurther below with reference to FIG. 4). Alternative reference lines 36are also provided on the inner surface 30. The reference lines 34 arenot intended to be visible on the outer surface 32 but are shown in FIG.2 as dashed lines 34 for clarity.

Electrical contacts 38 are provided on the inner surface 30 of theundergarment and are conductively connected to corresponding electricalcontacts 40 on the outer surface 32.

Velcro® straps 42 (i.e. hook and loop fasteners) are provided on eitherside of the undergarment and an arcuate shaped portion 44 (correspondingto reference numeral 20 in FIG. 1) is provided at its lower end.

In use, replaceable electrodes for contacting a user's skin arepositioned on the skin facing surface of the undergarment with the aidof the reference lines 34. For some users (i.e. because of their size ofother specific requirements) replaceable electrodes A and D arepositioned to correspond with the alternative reference lines 36.

The undergarment is then fitted to the user's leg by wrapping andsecuring the Velcro® straps 42 around the thigh and aligning the arcuateshaped portion 44 with the top of the patella. The electrical contacts38 on the inner surface 30 therefore make electrical contact with thereplaceable electrodes which in turn contact the user's skin over thequadriceps muscle. The replaceable electrodes electrically connect tothe contacts 38 by means of mating contacts or a conductive adhesivelayer.

The contacts 38 are electrically connected to contacts 40 on the outersurface 32 of the undergarment. The electrical contacts 38 and 40preferably comprise conductive stud fasteners which are fixed on andextend through the fabric of the undergarment. The flat surface of thestud fastener presents on the inner surface 30 whereas a male or femalepart of the stud fastener presents on the outer surface 32.

The reference lines 34 and 36 and the electrical contacts 38 arepositioned to correspond with anatomical features such that upon correctapplication and alignment of the garment to the leg, electrodes ofappropriate size, shape, orientation and electrical connection arepositioned on the leg.

FIG. 3 shows both the inner surface 50 and outer surface 52 of anover-garment which is worn over the undergarment of FIGS. 1 and 2. Theinner surface 50 is provided with stud fasteners 54 which areelectrically connected to a stimulation device 56. Control means 58 forcontrolling the stimulation device are provided on the outer surface 52of the over-garment.

In use, the over-garment is attached to the undergarment via theirrespective stud fasteners 54 and 40. A conductive path is thereby formedbetween the stimulation device 56 and the replaceable electrodes on auser's skin.

The over-garment is a flexible fabric envelope containing the stimulatorelectronics and a battery. The control means 58 comprises an integralLiquid Crystal Display (LCD) and button control panel located on theouter surface 52 of the over-garment. The user controls include two upand down controls for medial and lateral muscles. The stimulatorinternally re-maps these controls depending on whether it is operatingon a left or right undergarment. For example, on a left undergarment,the rightmost amplitude control sets the intensity of the medial muscle,whereas on the right undergarment it is the leftmost amplitude controlwhich sets the intensity of the medial muscle. This is particularlyimportant when the sequencing of the muscle activation is required torecruit medial before lateral muscles.

FIG. 4 shows four replaceable electrodes A, B, C and D which arepositionable within the undergarment and, in use, contact the user'sskin. This figure illustrates where each electrode typically locates onthe right leg when the undergarment is applied in accordance with theuser instructions. Electrode A covers the upper quadriceps area whileelectrodes B and C together cover the lower quadriceps area. Electrode Clocates medially while B locates more centrally and extends laterally.Electrode D has a dog-leg shape and is positioned to recruit the morelateral fibres of the quadriceps.

Electrode A: This is a large electrode in the shape of a rectanglemeasuring 20 cm×10 cm (with rounded corners) positioned so as to extendacross the upper quadriceps as illustrated. The electrode extendsequidistant either side of the mid-thigh location mark and its loweredge is displaced 20 cm from the midpoint of the patellar locatingarcuate portion described previously. An alternative position forelectrode A is also provided to accommodate taller users which is 22 cmfrom the patellar mark. This electrode has a surface area ofapproximately 196 cm².

Electrode B: This electrode is in the shape of a rectangle measuring 10cm×7.5 cm (again with rounded corners) positioned so as to extend acrossthe lateral portion of the quadriceps muscle close to the patella. Themajor midline of this electrode is 7 cm from the patellar mark while theminor midline is displaced 4 cm laterally from the midline locating markon the garment. This electrode has a surface area of approximately 74cm².

Electrode C: This electrode is in the shape of a rectangle measuring 14cm×6.5 cm (again with rounded corners) which extends along the medialportion of the quadriceps muscle close to the patella. The major midline of the electrode is displaced 6 cm from the midline locating markon the garment and the minor midline of the electrode is displaced 7 cmfrom the patellar locating edge. This electrode has a surface area ofapproximately 82 cm².

Electrode D: This is a small electrode which locates laterally on theupper leg. It is preferably dog-leg in shape and can be used on eitherthe right or left leg. This electrode has a surface area ofapproximately 57 cm². An alternative, more lateral, position for theelectrode is provided on the garment to accommodate thighs of largergirth.

In this non-limiting example, the total area of all four electrodes isapproximately 410 cm². However, it will be appreciated that dimensionsof the electrodes can be varied and are typically greater than 300 cm².The electrodes are as large as possible to recruit the target musclewith the minimum current density at the skin. It is clear that most ofthe anterior surface of the thigh is covered by one or other of theelectrodes and this is very different to the established practice whichfavours much smaller electrodes which require more accurate placement.Using these much larger surface area electrodes has proved successful inrecruiting the maximum number of muscle fibres whilst minimising currentdensity at the skin.

The relative sizes and positions of electrodes when in place on the bodydefine the current pathways which can be created. When electrodes areplaced on a planar body surface then the penetration of the electricfield is not as good as when electrodes are placed on a curved surface.By choosing electrode positions which establish current pathways whichtransect the body structure then stimulation of deeper tissue can beachieved. The thigh, in simple terms, is a cylindrical formation withlittle curvature along its length but high curvature around itscircumference. Accordingly, by positioning one electrode displacedcircumferentially from another electrode located at the anterior thighmidline we achieve deeper penetration. The appropriate dimensioning ofthis displacement with respect to relevant anatomical markers ensuresthat selected nerves are stimulated.

The preferred positioning of the replaceable electrodes is as follows.One large electrode covering the upper fibres of the quadriceps and thefemoral nerve and (its upper branches). Two lower electrodes cover thedistal quadriceps fibres. The inner lower electrode is sized and shapedso that it covers the lower fibres of the vastus medialis. This gives usthe option to zone in on this muscle separately for part of therehabilitation. The fourth electrode is an outer lateral electrode andlies on the extreme lateral fibres of the quadriceps and its mainfunction is to direct the impulses from the combination of electrodes ina different direction. This electrode is displaced circumferentiallyfrom the anterior thigh midline and when used in conjunction with someor all of the other electrodes creates current paths with transect thethigh thereby stimulating deeper tissue. This allows rehabilitation of agreater variety of fibres within the muscle.

The large surface areas of these electrodes allow for a more comfortablecontraction, because the skin current density is reduced. Furthermore,this reduces the necessity for precise adjustment of electrodepositioning between individuals.

FIG. 5 shows the apparatus in use whereby the user can control thestimulation of the quadriceps muscle.

The apparatus comprises an over-garment having an integrated stimulationdevice which includes integrated electronics, an LCD display, usercontrols and a battery. The integrated nature of the electricalconnections means that the user does not have to make individualconnections between the stimulator terminal and each replaceableelectrode. Apart from removing the requirement to select electricalconnections, such a system can automatically change between left leg andright leg modes by transposing connections and the mapping of usercontrols and display elements.

While the apparatus may work with a simple single or dual channelstimulator, it is preferable that the apparatus is connected to anadvanced stimulator, as more fully explained below. This allows theselection of any subset of electrodes as one electrical pole (i.e. as acathode) and any other subset as the other electrical pole (i.e. as ananode) and therefore creates a choice of current pathways through thethigh.

The success of traditional Electrical Muscle Stimulation (EMS) systemsdepend on the relative positions of the array electrodes on the body,and the correct connection to signal sources in the stimulator. Anyerrors could lead to a completely different current path in the bodyfrom that intended. For this reason these techniques are not suitablefor general use with traditional exposed leadwire systems which areprone to human error.

The present apparatus solves this problem by providing an electrodelocating means, and an electrode connection means within an integratedtamperproof garment. The electrode selections and the timing thereof areas follows.

The preferred apparatus has an integrated two-channel electronic musclestimulation garment operating with four replaceable skin electrodes.Preferably, the stimulation signal takes the form of a modulated pulsetrain, utilising a symmetric biphasic pulse with interphase interval,operating under constant current control. Each stimulation pulse may bedivided into a number of time segments, called timeslots, and differentelectrode selections can be made under software control for eachtimeslot.

The general effect of this approach is to achieve larger effectiveelectrode areas by combining the areas of individual electrodes. Thisreduces skin current density for a given stimulation current level. Theeffect of dividing the pulse into timeslots with different electrodeselections is to vary the phase charge seen by each electrode andtherefore the intensity of stimulation associated with each electrode.

Where electrodes are combined to form an anode or cathode, then thecurrent density at the skin is reduced, thereby reducing skin sensationcompared to the situation of using only one of the electrodes.

Circuits comprising an anode set and a cathode set can be createdwhereby the anode and cathode have unequal areas. The current densityfor the lower area group is therefore higher than for the high areagroup.

Where electrodes are combined to form an anode or cathode, then thespatial distribution of the current in the quadriceps area is changedbecause of the dispersion of the current over the larger electrode area.

The apparatus operates with predetermined electrodes with a defineddesign area and shape. Therefore the current densities and currentdistributions between the electrodes are controlled and cannot bechanged by the user. At worst case, the user could apply the wrong sizeor shape electrode in the wrong position on the undergarment. In thisworst case, the maximum current density still cannot exceed the designlimit although the effectiveness of the stimulation would possibly bereduced. A user cannot change the connections to the electrodes or alterthe sequencing of the stimulation signals applied to the electrodes. Theopportunities for error are therefore greatly reduced.

Tables 1 and 2 in FIG. 6 show examples of electrode sequencing. “H”indicates the electrode sources current for the period, “L” indicatesthe electrode sinks, while “X” indicates the electrode is unused in theperiod.

In one example of the operation of the apparatus (see Table 1), Channel1 has a stimulation pulse phase duration of 100 μS and a consistentelectrode pattern is maintained throughout. Electrodes A, B and D areelectronically combined together to form a single electrode whileelectrode C is selected as the opposite pole. This has the effect ofreducing the current density in A, B and D compared to C, therebyincreasing the relative stimulation of the medial quadriceps compared tothe rest of the muscle group.

Meanwhile, Channel 2 has a pulse phase duration of 400 μS, which isdivided into two timeslots, of 300 μS and 100 μS respectively. Theelectrode selection pattern for the first timeslot groups electrodes Band C together as a single electrode with electrode A as the oppositepole electrode. Electrode D is unconnected for the first timeslot. Thisselection effectively creates a single large electrode at the lowerquadriceps operating with the single large electrode A at the upperquadriceps. For the second timeslot only, electrodes A and D areselected. This directs a stimulation signal to the lateral D electrode,increasing the lateral recruitment to the muscle contraction. Channel 2therefore stimulates the quadriceps in general, with a bias towards thelateral components of the muscle.

The electrode drive patterns for channel 1 and channel 2 areautomatically changed by software such that channel 1 is operable by theleft hand amplitude controls when fitted on a right leg undergarment,and by the right hand amplitude control when fitted on a left legundergarment. In this way, the medial part of the muscle is alwaysoperable by the medial amplitude control, whereas the lateral musclegroup is always operable by the lateral amplitude control.

A further example of electrode sequencing together with the currentpatterns at each electrode is provided in the second table in FIG. 6with the corresponding current patterns for each electrode shownunderneath. (The current patterns are not to scale in either time orcurrent amplitude)

Various modifications and improvements may be made without departingfrom the scope of the present invention.

For example, an alternative to the arcuate shaped portion whichcorresponds with the shape of the patella could be a donut shapedlocator at the distal end of the undergarment. However this design, aswith any thigh garment with a knee splint, would tend to pull on theundergarment proximally when the knee joint flexes.

Two versions of the undergarment could be provided, one for the rightand one for the left leg. An identical array of stud fasteners would beprovided on either type however a different subset of contacts would beused for the left and right versions. An undergarment would be factoryconfigured for left or right use by electrically linking one studfastener in one of two alternative positions. This would allow thestimulator electronics to detect which undergarment is connected andthereby direct the appropriate signals to each element of the studarray. Alternatively, unused stud fasteners could be insulated with aninsulating cover.

While the preferred apparatus includes the over-garment having anintegrated stimulator device, it could be adapted for use with variousconventional electrical stimulation units. A simple single or dualchannel stimulator device could be connected to the appropriateelectrodes using, for example, leadwires terminating in stud fastercontacts. For general quadriceps rehabilitation both channels would beused.

In the case where a clinician needs to zone in on extra rehabilitationof the vastus medialis the medial channel is used alone. When bothchannels are used there is a default feature that brings in thecontraction of the vastus medialis before the rest of the bulk of thequadriceps. This is particularly useful for the person with an unstablepatella. If the patella is prone to dislocation it will invariably be inthe lateral direction. In this embodiment the patella is pulled slightlyinwards and then upwards, ensuring stability of the patella.

While the electrode configuration described has several advantages it isalso possible to use smaller electrodes of conventional round and/orrectangular shape. Accurate location of such electrodes can still beachieved by a suitable garment which includes the anatomical referencemeans described (i.e. the patellar location arcuate portion). Theapparatus may include at least one electrode and may include an array ofelectrodes which will all locate correctly if referenced to the locatingmeans.

Any form of electrical therapy or biological signal detection could beapplied to this garment such as TENS, EMG etc. Indeed, a combined dualfunction stimulation and receiving device could be incorporated into thegarment (i.e. a combination of the first and second aspects of theinvention).

Garments for other muscle groups in the body could also be includedprovided there was a fixed relationship between the locating surfaceanatomical feature and the intended muscle, muscle group or nerve tothis group. Examples of this may include the reliable location of thecommon peroneal nerve just below the fibular head or the ulnar nervebehind the medial condyle of the humerus. There can also be a specificrelationship between anatomical features and the movements of a musclewhether it displaces with movement or simply shortens in an isometriccontraction.

1. Muscle stimulation apparatus for applying an electrical current tothe leg muscles comprising: a garment adapted to cover an upper area anda lower area of the quadriceps; a stimulation device for generating amuscle stimulating current in the form of a pulse train connectable toat least three fixed electrical contacts on said garment, the garmentbeing shaped to correspond, in use, with a particular anatomical featureon a user to ensure accurate and repeatable positioning of the garmentwith respect to the upper and lower areas of the quadriceps muscles tobe treated such that one fixed electrical contact covers upper fibres ofthe quadriceps and two fixed electrical contacts cover lower fibres ofthe quadriceps close to the patella; the stimulation device furthercomprising control means for selectively directing stimulating pulsesbetween said three or more fixed electrical contacts, and whereindifferent fixed electrical contact selections can be made under softwarecontrol for selecting any subset of the fixed electrical contacts in thegarment to form one electrical pole, and any other subset or all of theremaining fixed electrical contacts in the garment as the oppositeelectrical pole so as to create pulse sequences comprising stimulatingpulses capable of being directed through six different pathways betweenthree of said fixed electrical contacts.
 2. Apparatus according to claim1 wherein the garment is marked with one or more reference lines to aidthe accurate and repeatable positioning of the garment with respect tothe quadriceps.
 3. Apparatus according to claim 1 wherein thestimulation device is adapted such that it is interactable with thegarment to determine whether it is a left-leg or right-leg garment. 4.Apparatus according to claim 1 wherein the garment has an arcuate shapededge at its distal end to correspond with the top of the patella. 5.Apparatus according to claim 2 wherein at least one reference line isalignable with a notional line extending upwardly from the centre of thepatella.
 6. Apparatus according to claim 1 wherein the garment consistsof an undergarment and an over-garment, the undergarment having at leastthree fixed electrical contacts on its skin-facing surface conductivelyconnected to corresponding fixed electrical contacts on its oppositesurface which, in turn, are conductively connected to contacts on theover-garment.
 7. Apparatus according to claim 6 wherein, stud fastenerswhich are fixed on and extend through the undergarment provideelectrical connections between the undergarment and the over-garment. 8.Apparatus according to claim 1 wherein the fixed electrical contacts aredisplaced circumferentially to establish current pathways which transectthe neuromuscular area.
 9. Apparatus according to claim 1 wherein thecontrol means includes user programmable software for controlling theduration of the stimulating pulses and their sequencing between thefixed electrical contacts.
 10. Apparatus according to claim 1 whereinthe control means includes user programmable software which allows theuser to map control buttons on the garment such that current applied toa medial and a lateral quadriceps muscle is controllable by a medial anda lateral control button respectively.
 11. Apparatus according to claim1 wherein the connections between the stimulation device and theplurality of fixed electrical contacts on said garment are preset andnon-alterable by the user.
 12. Apparatus according to claim 11 whereinthe connections between the stimulation device and the plurality offixed electrical contacts on said garment are integrated within thegarment itself.
 13. Apparatus according to claim 1 wherein eachstimulation pulse is divisible into a number of timeslots and differentfixed electrical contact selections can be made under software controlfor each timeslot.
 14. Apparatus according to claim 6 wherein each fixedelectrical contact on the undergarment is conductively connectable to askin engaging electrode.
 15. Apparatus according to claim 14 whereinfour fixed electrical contacts are employed.
 16. Apparatus according toclaim 14 wherein at least one fixed electrical contact has a differentsurface area from the other skin engaging electrodes.
 17. Apparatusaccording to claim 14 wherein the combined surface area of the skinengaging electrodes is at least 300 cm².
 18. Apparatus according toclaim 16 wherein the skin engaging electrode having the greatest surfacearea extends across the upper quadriceps.
 19. Apparatus according toclaim 18 wherein, at least one of the remaining skin engaging electrodescovers at least part of the lower fibres of the vastus medialis. 20.Apparatus according to claim 18 wherein, at least one of the remainingskin engaging electrodes covers at least part of the lateral fibres ofthe quadriceps.
 21. Apparatus according to claim 14 wherein one of theskin engaging contacts is generally dog-leg shaped.
 22. Apparatusaccording to claim 14 wherein at least one of the skin engagingelectrodes is generally rectangular in shape.
 23. Apparatus according toclaim 14 wherein, the skin-facing surface of the undergarment comprisesreference lines corresponding to the shape of each skin engagingelectrode to aid accurate positioning of the skin engaging electrodes bythe user.